An archive of correspondence from George Washington Carver (1864-1943) to Goode Chesterfield Blanks will feature in a historical manuscript sale at Heritage Auctions in New York.
It is valued in excess of $70,000.
The lot consists of around 200 letters, cards and bills dating to between 1908 and 1943.
Carver was born into slavery in Missouri in 1864 but went on to have a long and distinguished career as America's foremost agricultural scientist.
He is particularly well regarded for his work in convincing farmers in the American south to switch from cotton, which was destructive to the soil and difficult to cultivate, to sustenance crops such as peanuts.
Carver met Blanks, a local farmer, in Alabama in the 1920s and the two men became firm friends - remaining in touch throughout their lives.
Another archive of memorabilia pertaining to Carver is due to appear at Swann Auction Galleries on March 27 with a $120,000 estimate.
A letter of attorney signed by the author Herman Melville, the author of Moby Dick, in 1847 is estimated to make $25,000-35,000.
Melville was keen to publish his novel Omoo in Britain and enlisted the help of a lawyer. He was successful in his application and the book was published later that year.
The April 3 sale also includes an archive of 24 handwritten letters by Mahatma Gandhi, valued at over $100,000.
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